INFLUENCES OF PLANKTON COMPOSITION ON EXPORT PRODUCTION: A MODELLING APPROACH

The export of carbon from the surface water is substantially influenced by the composition of the plankton community, which can shift dramatically seasonally and from year to year. A better understanding of the links between phytoplankton type, food web structure, and export efficiency is required to estimate global export production and to predict potential future responses of the carbon cycle to climate change. In this study, a vertically resolved, dynamic plankton ecosystem model of the NE subarctic Pacific is used to explore the effect of changes in the composition of the planktonic community on export production. Model results indicate that changes in the size composition of phytoplankton and the type of dominant zooplankton have the strongest effect on carbon fluxes. We discuss the ecosystem response to changes in plankton composition with particular emphasis on f-ratio and export production.